Performance Analysis and Optimization of Large Caliber Davis Gun Based on Interior Ballistic Two‐Phase Flow Method

Davis gun as a representative experimental method for achieving hypersonic velocities in large‐scale, high‐mass systems effectively addresses the demands for scalable and reproducible dynamic experiments. However, due to the geometric constraints and operational principles inherent to Davis gun launch devices, the mechanistic interpretation of parameter interactions under multi‐physics coupling effects remains challenging. To address this, the present study establishes a coupled gas‐solid two‐phase flow model for the interior ballistics of the Davis gun and employs a multi‐objective optimization algorithm to conduct quantitative analysis of multi‐parameter interactions. Comparative experimental validations across multiple caliber configurations demonstrate that the proposed two‐phase flow model achieves remarkable prediction accuracy for chamber pressure and velocity fields, with computational results showing excellent consistency with experimental data (error margin within 5%). Transient analysis of combustion kinetics and propellant gas distribution characteristics reveals that the chamber flow field in the Davis gun exhibits a bidirectional expanding asymmetric distribution pattern, fundamentally differing from the unidirectional flow evolution observed in conventional launch devices. Multi‐objective parameter optimization results indicate that the feasible design space exhibits pronounced aggregation characteristics. Through correlation analysis of the feasible region and coefficient matrix, a multi‐parameter influence propagation pathway map is constructed, thereby providing a systematic technical pathway and engineering paradigm for multi‐objective optimization design of Davis gun launch interior ballistics.